Abstract:
실시예들에서, 무선 수신기는 펌웨어에 의해 제어되는 하드웨어-기반 고속 푸리에 변환(FFT) 엔진을 사용한다. FFT 엔진은 작업 목록에 저장된 작업들을 실행시킨다. 각각의 작업은 신호의 상이한 일부분, 예컨대 하나 이상의 직교 주파수 분할 변조(OFDM) 심볼들과 연관된다. 각각의 작업은, 상기 엔진이 상기 신호의 상기 연관된 일부분, 상기 일부분에 대한 포인터, 그리고 출력을 저장하기 위한 메모리에 대한 다른 포인터를 프로세싱하도록 구성하기 위해 FFT 엔진을 위한 구성 정보를 포함할 수 있다. 상기 작업 목록은 펌웨어 제어될 수 있다. 작업 목록으로부터 작업들을 판독하여 실행시키기 위해 펌웨어에 의해 구동되는 구성가능한 하드웨어 파트로 상기 FFT를 분할하는 것은 FFT 프로세스의 속도를 높일 수 있고, 더욱 유연성 있게 한다. 서브-캐리어들을 그들의 에너지들에 따라 정렬하기 위한 하드웨어 비콘 정렬기가 상기 FFT 엔진에 커플링될 수 있다.
Abstract:
무선 통신 시스템에서 확인응답 메시지를 전송하기 위한 방법이 개시된다. 제 1 신호는 송신기로부터 제 2 신호가 수신되기 이전에 수신된다. 디코딩된 제 1 데이터는 제 1 신호로부터 추출된다. 제 3 신호는 디코딩된 제 1 데이터를 인코딩하고 변조함으로써 생성된다. 제 2 신호는 제 2 심벌들을 생성하기위해 복조된다. 제 3 신호 및 제 2 심벌들은 코릴레이팅된다.
Abstract:
Systems and methods for canceling interference in a communication system are described. A signal that comprises current data from a current access point and secondary data from one or more secondary access points is received. The secondary data is demodulated using one or more secondary channel estimates if a signal metric is less than a predetermined threshold. Interference in the received signal is canceled using the demodulated secondary data if the signal metric is less than the predetermined threshold. The received signal with the interference canceled is demodulated using a current channel estimate to obtain the current data. The method for interference cancellation may use the same hardware resources and processing available for receiving data from a single access point.
Abstract:
A technique for generating a reduced bit-width in a signal generated by a first-type modulator in a communication apparatus that includes two distinct modulators. In particular, the communication apparatus includes a first modulator adapted to generate a first modulated signal quantified to a first bit-width, a second modulator adapted to generate a second modulated signal quantified to a second bit-width that is less than the first bit-width, and a device to generate a third modulated signal comprising a combination of the first and second modulated signals. In an exemplary implementation, the first modulator includes an OFDMA modulator, the second modulator includes a CDMA, and the combining device includes an IFFT. Additionally, an apparatus for processing a communication signal includes a tasklist cache memory having a tasklist, a processor adapted to provide a task to the tasklist, and a communication module adapted to fetch the task from the tasklist, and process the communication signal based on the retrieved task.
Abstract:
In embodiments, a wireless receiver employs a hardware-based Fast Fourier Transform (FFT) engine controlled by firmware. The FFT engine executes tasks stored in a task list. Each task is associated with a different portion of a signal, for example, one or more Orthogonal Frequency Division Modulated (OFDM) symbols. Each task may include configuration information for the FFT engine for configuring the engine to process the associated portion of the signal, a pointer to the portion to be processed, and another pointer to the memory for storing the output. The task list may be firmware controlled. Division of the FFT into a configurable hardware part driven by firmware to read and execute the tasks in the task list may speed up the FFT process and make it more flexible. A hardware beacon sorter may be coupled to the FFT engine to sort the sub-carriers according to their energies.
Abstract:
Techniques for performing time tracking in a communication system utilizing a cyclic prefix are described. In an aspect, a receiver may detect for large timing errors based on early and late received samples obtained with early and late FFT windows, respectively. The receiver may derive first and second channel impulse response (CIR) estimates based on the early and late received samples, respectively, determine an early channel energy based on the first CIR estimate, determine a late channel energy based on the second CIR estimate, compute an update amount based on the early and late channel energies, and update the FFT window position based on the update amount. In another aspect, the receiver may perform time tracking with an inner time tracking loop (TTL) and an outer TTL. The receiver may update the FFT window position in coarse steps with the outer TTL and in fine steps with the inner TTL.
Abstract:
A method for sending an acknowledgment message in a wireless communication system is disclosed. A first signal is received before receiving a second signal from a transmitter. Decoded first data is extracted from the first signal. A third signal is produced by encoding and modulating the decoded first data. The second signal is demodulated to produce second symbols. The third signal and the second symbols are correlated.